topic Re: Reduce the number of polygons for an exterior scene in 3ds Max Forum

Reduce the number of polygons for an exterior scene

Anonymous — Thu, 05 Oct 2017 17:08:41 GMT

Hello,

I am trying to reduce the polygon count of a huge model (around 230 000 triangles according to Simplygon) which shows an exterior area with buildings and lamps. Everytime when I try to start the reduction 3dsMax 2018 crashs and I cannot find any way to reduce the polygons (tried it with different software like Polycrunch, Simplygon, Rhino, Meshlab without any outcome).

The original file is an exterior lighting scene (dlx-file: Dialux). From this I made a 3D-PDF-screenshot with Adobe Acrobat 9 Pro Extended. I converted the 3D-PDF to an FBX with SimLab and want to import that FBX into Unity to develop a VR-app. In Unity I realized that the model is to huge to work with (got only around 2.1 fps).

The CPU of my PC is an i7-7700HQ, so that should be enough to develop a VR-app. The polycount is about around 230 000 triangles (according to Simplygon).

I am not sure if this is enough information to help me because I never used 3ds max before. So let me know if more is needed. Would be great if someone could help!

Cheers

Max

Re: Reduce the number of polygons for an exterior scene

irishman_team_kilber — Fri, 06 Oct 2017 20:12:26 GMT

have you added an Optimize modifer? this will reduce the poly's 10 fold! https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/3DSMax/files/GUID-4D61E710-9D95-4469-B05C-8C8A126D59CC-htm.html

Re: Reduce the number of polygons for an exterior scene

Anonymous — Thu, 12 Oct 2017 17:04:44 GMT

I really tried but 3dsmax crashs everytime.

I am not sure but I think the model I've got is made out of a countless amount of small objects. I can select single party (about 20 polys) and modify them but when I select all it is crashing.

So could that be the problem? That my model is made out of a lot of objects?

Re: Reduce the number of polygons for an exterior scene

KurtNeuburger — Thu, 12 Oct 2017 18:08:31 GMT

We use models larger than this on a regular basis. The poly count should not be a problem if you have a decent computer. We deal with scenes in the millions of polygon range with no issue. And lately we have been preparing them in 3ds Max for use in Unity (and ultimately HoloLens) as well. The approach typically goes like this: import scenes into Max, delete unnecessary objects, remodel simple objects that have way too many polygons, remove internal hollows and other geometry that is not seen typically, and finally run the complex objects through PolygonCruncher adjusting settings to maximize output and minimize polys. We use PolygonCruncher because we have found it easier and quicker than the optimize commands inside Max.

We've been pretty successful with reducing scenes from 5-8 million polygons down to the 100-300k poly range. And they work just fine in Unity.

Re: Reduce the number of polygons for an exterior scene

Anonymous — Thu, 19 Oct 2017 12:54:47 GMT

Okay, maybe an other question: is my computer decent enough?

The specs are:

GPU: Nvidia GeForce GTX1060

CPU: i7-7700HQ 2,8 GHz

RAM: 16 GB

Windows 10 Home 64-bit

I thought that should be enough but even the import of the file into 3ds Max takes other 15 minutes. Fore me there are two possible reasons: either my pc is not good enough or the model was built badly. Is that possible?

Thanks for your help!

Re: Reduce the number of polygons for an exterior scene

KurtNeuburger — Thu, 19 Oct 2017 13:22:30 GMT

Well, your graphics card is not on the approved list for 3ds Max 2018, so that may or may not be your problem. Your CPU is rather slow as well, so that could contribute to the slow import. We used to run on processors in the 2.5-3ghz range and regularly had to wait for large scenes to load.

Can you share the file here that you are trying to import?

Re: Reduce the number of polygons for an exterior scene

Anonymous — Thu, 19 Oct 2017 13:59:22 GMT

Here it is!

Thanks for your help! I am really curious about your answer.

Re: Reduce the number of polygons for an exterior scene

KurtNeuburger — Thu, 19 Oct 2017 14:54:13 GMT

So, aside from your computer limitations...

It took me about 20 minutes to import the fbx as well. I think the problem is the massive number of entities in the scene (84,000+). Being that this is a scene of what looks like an entire airport, the time it takes to clean it up in Max will be substantial, and an automated tool to clean up and simplify the whole scene in one shot is a little unrealistic.

Even the "3D" elements in the scene are not actually 3d models, they look to be simple planes. For instance, the small plane "model" is made up of thousands of mesh objects that are just individual 2d planes. It looks like wherever this scene came from originally, it was not compatible with a 3ds Max like software package. Or it was exported incorrectly. Even if you could clean up the scene significantly, with no real 3d objects, it will most likely never produce any good renderings or a viable VR experience.

It would be easier to redraw the entire airport than try to work with this scene as it is.

I did a bit of searching in the old google machine. I don't see a solution for importing Dialux models into 3ds max. There are several references for going in the other direction. I don't know anything about Dialux, but from what I am seeing, it seems like a model of this size would most likely never have been created in Dialux natively. I'm guessing it was transferred into Dialux at some point before you got the model. I'd suggest hunting down the original model and try to get that into 3ds Max. If that is not a possibility, the next best option would be to recreate the entities in 3ds Max after your import, and then delete all of the nonsense geometry that comes in on the import. REalistically, you will probably end up with more polygons when you are done, but a tiny fraction of the number of objects, so it will run much faster, look better, and actually be useful in VR.

Good luck!

Re: Reduce the number of polygons for an exterior scene

Anonymous — Thu, 19 Oct 2017 16:13:04 GMT

Really great answer! That's something I can work on.

I will sleep a night on it and hopefully know tomorrow how to continue.

Thanks for your really great and detailed help!

PS: There is a way to transfer a Dialux file into Unity (or 3ds Max), described here: http://info.tuwien.ac.at/bausim/conftool/ferschin-2010-exploring_the_potential_of_game_engines-141.pdf
The clue is to get a really old version of Adobe Acrobat and to make a '3D-PDF-screenshot' of the Dialux file. Then it is possible to import the PDF to SimLab and transfer it to a FBX/OBJ/...

Re: Reduce the number of polygons for an exterior scene

KurtNeuburger — Thu, 19 Oct 2017 16:51:17 GMT

Well, but that is what you did and it resulted in an unusable file. 😛

Re: Reduce the number of polygons for an exterior scene

marksman123 — Fri, 20 Oct 2017 19:06:34 GMT

Use instances when possible, and also use the ProOptimizer modifier on objects that have an unnecessary amount of polygons, especially on objects way off in the distance.

Hope that helps!

Re: Reduce the number of polygons for an exterior scene

rode3d — Wed, 13 Nov 2019 00:00:39 GMT

Here's a great tool for creating multiple proxies automatically and easily reduce the number of polygons and file size.

Q-Proxies 3dsMax plugin: http://www.splinedynamics.com/q-proxies/